Ellesmere soil resources : a soil resource survey and interpretation of part of Lake Ellesmere margin, Canterbury, New Zealand

Abstract

Various techniques were used to map and describe the extremely variable soil pattern associated with the fluvial-lacustrine sediments in the Lake Ellesmere area. Recent concepts of defining and relating soil mapping units and soil profile classes were used to select soil mapping units. At the map scale chosen (1:10,000), the detailed soil pattern could not be resolved in some areas. Accordingly, many areas have been mapped as complexes, and their contents are illustrated by means of detailed grid surveys.

One soil family and thirteen soil series were identified in the soil survey. Many previously recognised series were redefined and as a result eight new soil series were proposed. Under the New Zealand system of classification 75% of the soil profile classes were identified as Skeliform soils, and the remaining 25% were Madentiform, Palliform, Fulviform and Organiform soils. The same soil profile classes covered three soil orders under the American system of classification. Seventy percent were Entisols, 24% Inceptisols, and 6% Histosols.

The soils were described and their properties discussed in terms of environmental, morphological, chemical and mineralogical parameters. Differences between soils were attributed to variations in soil age, parent materials, and moisture regimes. Other factors discussed included texture, flooding, drainage, and land management.

Soil resource survey interpretations were prepared for agriculture, wildlife and recreation. The potential for this type of soil resource information is discussed and recommendations for future research proposed.

Recommendations are made regarding the use of series differentiae in fluvial-lacustrine environments and some alternative methods of assessing soil moisture regimes proposed.

The soil survey illustrated a need for high quality aerial photographs, especially colour, when mapping soil resources in an area such as this, which is very flat and poorly drained.